1. Field of the Invention
The present invention relates to a straddle-type vehicle and, in particular, to an air intake passage for a case housing a continuously variable transmission in an engine unit of the straddle-type vehicle.
2. Description of Related Art
A straddle-type vehicle in which air is sent into a case housing a continuously variable transmission to cool a belt of the continuously variable transmission is proposed, for example, in Japanese Examined Utility Model Publication No. 7-022391. In JP 7-022391, an air cleaner for cleaning air to be sent to an engine is disposed at the highest position (at the rear of a steering head) in a vehicle body frame, and an air intake port of an air intake duct for sending air into the case of the continuously variable transmission is arranged at the front of the air cleaner. With this configuration, water and the like can be prevented from entering the engine and the case of the continuously variable transmission even when the vehicle travels in a damp area.
However, the air intake duct of JP 7-022391 is passed in front of an air intake pipe for sending air into the engine and extends upward, and has an air intake port positioned at the front of the air cleaner. The air intake duct is thus elongated by a length corresponding to the elongation of the air intake duct to the front side of the air cleaner, which may raises the possibility that sufficient air intake efficiency will not be acquired.